816 research outputs found

    The effective electrical conductivity of a two-phase liquid-metal flow

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    Electrical conductivity of two phase liquid metal flow in magnetohydrodynamic generato

    Adaptation of the quantitative PCR method for the detection of the main representatives of cereal grain mycobiota

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    The content of fungal DNA and mycotoxins in cereal crops (31 varieties of wheat, oats, and barley) was quantitatively determined and used for comparative characterization of grains. The quantitative PCR has been adapted for the analysis of the target DNA of Alternaria spp., Bipolaris sorokiniana (B. sorokiniana), Fusarium graminearum (F. graminearum), F. culmorum, and F. sporotrichioides fungi, which are often present in mycobiota of small grain cereals. The content of DNA of aggressive pathogen B. sorokiniana was determined using quantitative PCR for the first time. The DNA of Alternaria fungi was found abundantly in all grain samples, but its content in the oat was significantly higher compared to barley and wheat (5 and 9 times higher, respectively). In barley grain, the content of B. sorokiniana DNA was on average significantly higher than in the grains of oats and wheat. The presence of F. graminearum DNA was established in all the analyzed grain samples while the F. culmorum DNA was found in 70% of the oat’s samples and in all samples of barley and wheat. Mycotoxin deoxynivalenol (DON) produced by these fungi was detected in all analyzed cereal grains in a range from 77 to 4133 μg/kg. The DNA of F. sporotrichioides was detected in 70% of oats and 50% of barley samples but was not found in wheat. The T-2 toxin produced by this fungus was detected in 45% of all samples within the range from 2 to 89 μg/kg. The statistically significant positive correlation with the Pearson correlation coefficient (r) equal to 0.49 (p<0.05) was observed between the amount of F. graminearum DNA and DON in the grain samples. Another significant positive correlation (r = 0.72, p<0.01) was found between DNA contents of Alternaria fungi and F. sporotrichioides in the grain samples. This leads to the suggestion that conditions for growth of these fungi in grain substrates are similar.The content of fungal DNA and mycotoxins in cereal crops (31 varieties of wheat, oats, and barley) was quantitatively determined and used for comparative characterization of grains. The quantitative PCR has been adapted for the analysis of the target DNA of Alternaria spp., Bipolaris sorokiniana (B. sorokiniana), Fusarium graminearum (F. graminearum), F. culmorum, and F. sporotrichioides fungi, which are often present in mycobiota of small grain cereals. The content of DNA of aggressive pathogen B. sorokiniana was determined using quantitative PCR for the first time. The DNA of Alternaria fungi was found abundantly in all grain samples, but its content in the oat was significantly higher compared to barley and wheat (5 and 9 times higher, respectively). In barley grain, the content of B. sorokiniana DNA was on average significantly higher than in the grains of oats and wheat. The presence of F. graminearum DNA was established in all the analyzed grain samples while the F. culmorum DNA was found in 70% of the oat’s samples and in all samples of barley and wheat. Mycotoxin deoxynivalenol (DON) produced by these fungi was detected in all analyzed cereal grains in a range from 77 to 4133 μg/kg. The DNA of F. sporotrichioides was detected in 70% of oats and 50% of barley samples but was not found in wheat. The T-2 toxin produced by this fungus was detected in 45% of all samples within the range from 2 to 89 μg/kg. The statistically significant positive correlation with the Pearson correlation coefficient (r) equal to 0.49 (p<0.05) was observed between the amount of F. graminearum DNA and DON in the grain samples. Another significant positive correlation (r = 0.72, p<0.01) was found between DNA contents of Alternaria fungi and F. sporotrichioides in the grain samples. This leads to the suggestion that conditions for growth of these fungi in grain substrates are similar

    Dynamic Causal Forests, with an Application to Payroll Tax Incidence in Norway

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    This paper develops a machine-learning method that allows researchers to estimate heterogeneous treatment effects with panel data in a setting with many covariates. Our method, which we name the dynamic causal forest (DCF) method, extends the causal-forest method of Wager and Athey (2018) by allowing for the estimation of dynamic treatment effects in a difference-in-difference setting. Regular causal forests require conditional independence to consistently estimate heterogeneous treatment effects. In contrast, DCFs provide a consistent estimate for heterogeneous treatment effects under the weaker assumption of parallel trends. DCFs can be used to create event-study plots which aid in the inspection of pre-trends and treatment effect dynamics. We provide an empirical application, where DCFs are applied to estimate the incidence of payroll tax on wages paid to employees. We consider treatment effect heterogeneity associated with personal- and firm-level variables. We find that on average the incidence of the tax is shifted onto workers through incidental payments, rather than contracted wages. Heterogeneity is mainly explained by firm-and workforce-level variables. Firms with a large and heterogeneous workforce are most effective in passing on the incidence of the tax to workers

    Phase equilibria and thermodynamic properties of oxide systems on the basis of rare earth, alkaline earth and 3d-transition (Mn, Fe, Co) metals. A short overview of

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    Review is dedicated studies of phase equilibria in the systems based on rare earth elements and 3d transition metals. It’s highlighted several structural families of these compounds and is shown that many were found interesting properties for practical application, such as high conductivity up to the superconducting state, magnetic properties, catalytic activity of the processes of afterburning of exhaust gases, the high mobility in the oxygen sublattice and more

    Welfare Effect of Closing Loopholes in the Dividend-Withholding Tax: The Case of Cum-cum and Cum-ex Transactions

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    We study the effect of reforms that close loopholes in the enforcement of the dividend withholding tax (DWT). We focus on a Danish reform enacted in 2016, and compare Denmark to its Nordic neighbors. Our main outcome of interest is the quantity of stocks on loan. Before the reform all Nordic countries have a strong spike in stocks on loan centered around the ex-dividend day. The magnitude is large: on average excess stocks on loan peak at around 4 percent of the public float. The spike in lending is consistent with the most popular DWT arbitrage schemes. After the reform the spikes in Denmark disappear, but they continue in the other Nordics. We interpret this as evidence that the reform was successful at eliminating DWT arbitrage. We consider the welfare effects of the reform. Using synthetic difference-in-difference we find that stricter DWT enforcement resulted in a 130 percent (approx. 1.3 bln USD annually) increase in DWT revenue in Denmark. We detect no changes in foreign portfolio investment or dividend policy. We also consider DWT arbitrage among 15 European countries between 2010-2019. We find evidence of DWT arbitrage in all countries that levy DWT, though there is strong heterogeneity across countries. Importantly, similar to Denmark, Germany’s 2016 reform has eliminated the spikes in lending completely. We validate our identification strategy by showing that we find no evidence of DWT arbitrage in the UK, which does not levy a DWT

    Antibodies to DNA stimulates death of mononuclear cells of healthy persons in vitro

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    We have shown that polyclonal antibody IgG to native DNA leads to increased levels of apoptosis of nonuclear cells of healthy persons in vitro. Possible biological role of antibodies to DNA is discussed

    Evaluation of selected lactic acid bacteria as starter cultures for gluten-free sourdough bread production

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    Received: January 30th, 2021 ; Accepted: April 8th, 2021 ; Published: May 19th, 2021 ; Correspondence: [email protected] is one of the most promising technologies for gluten-free bread. The selection of appropriate starter cultures for the production of gluten-free sourdoughs is of a great importance, since not all microorganisms can adapt equally to the same raw material. The aim was to create a new starter microbial composition for gluten-free sourdough preparation, allowing improving the quality and the microbiological safety of gluten-free bread. Screening was conducted on 8 strains of lactic acid bacteria (LAB) and 5 strains of yeast previously isolated from spontaneously fermenting rice and buckwheat sourdoughs. The strain S. cerevisiae Y205 had the highest fermentative activity and alcohols content. The lactic acid bacteria L. brevis E139 and L. plantarum Е138 were also experimentally selected for new gluten-free sourdoughs on the basis of acidity and volatile acids production and antagonistic activity. Two types of microbial composition were created and its influence on sourdough biotechnological indicators was studied. Sourdough with L. plantarum Е138 had in 1.2 times lower titratable acidity, in 3.4 times lower volatile acids content compared to sourdough with L. brevis E139. Alcohol content was the same in both sourdoughs similarly to yeast cells amount. Sourdough dough proofing time increased in 1.2–1.3 times compared to the control. Sourdough did not affect the specific volume, porosity and compressibility of gluten-free bread, but its sensory characteristics were improved. Bread made with sourdoughs had more pronounced taste and flavor, brighter crust color and better texture compared bread without sourdough. The microbiological safety of sourdough gluten-free bread was also increased, especially when L. brevis E139 was used

    Proactive management in the power industry: Tool support

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    Increasingly dynamic, non-linear and all too often chaotic changes in the global environment and tougher competition, including at the geopolitical level, call for radical transformations in strategic management of the power industry. The article provides the results of a study into proactive actions of energy company management, which are becoming increasingly important. The article offers a framework of concepts relating to proactive management and sums up ideas of a number of authors on diagnostics of weak signals as possible harbingers of threats to sustainable power industry development. The authors have determined a general approach to mechanisms of threat identification and developed methodological principles of shaping a corporate management model capable of reacting to new challenges. The article provides a thorough study of some components of the model and an assessment of factors that ensure successful implementation of the authors’ conceptual solutions in energy companies. © 2017 WIT Press.ACKNOWLEDGEMENT The work was supported by the Act 211 Government of the Russian Federation, contract № 02.A03.21.0006
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